/*  Mytget - A download accelerator for GNU/Linux
 *  Homepage: https://github.com/lytsing/Mytget
 *  Copyright (C) 2005- xiaosuo
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include <cstring>

#include "http.h"
#include "url.h"
#include "utils.h"
#include "macro.h"
#include "httpplugin.h"
#include "debug.h"

#define USER_AGENT "Mytget"

int HttpPlugin::get_info(Task *task) {
    Http http;

    http.set_timeout(task->timeout);
    http.set_log(&debug_log);
#ifdef HAVE_SSL
    if (task->url.get_protocol() == HTTPS) {
        http.set_use_ssl(true);
    }
#endif

    if (task->url.get_user() != NULL) {
        http.auth(task->url.get_user(),
                task->url.get_password() ? task->url.get_password() : "");
    }

    if (task->get_referer() != NULL) {
        http.header("Referer", task->get_referer());
    } else {
        http.header("Referer", task->url.get_url());
    }

    if (task->get_host() != NULL) {
        http.header("Host", task->get_host());
    } else {
        http.set_host(task->url.get_host(), task->url.get_port());
    }

    if (task->get_ua() != NULL) {
        http.header("User-Agent", task->get_ua());
    } else {
        http.header("User-Agent", USER_AGENT);
    }

    if (task->fileSize > 0) {
        // test the Range
        http.set_range(1);
    }

    if (task->proxy.get_type() == HTTP_PROXY) {
        if (task->proxy.get_host() == NULL) {
            return -1;
        }
        if (http.connect(task->proxy.get_host(), task->proxy.get_port()) < 0) {
            return -2;
        }
        if (task->get_host() == NULL) {
            http.set_host(task->url.get_host(), task->url.get_port());
        }
        if (task->proxy.get_user() != NULL) {
            http.proxy_auth(task->proxy.get_user(),
                    task->proxy.get_password() ? task->proxy.get_password() : "");
        }

        if (http.get(task->url.get_url()) < 0) {
            return -2;
        }
    } else {
        if (http.connect(task->url.get_host(), task->url.get_port()) < 0) {
            return -2;
        }
        if (http.get(task->url.get_encoded_path()) < 0) {
            return -2;
        }
    }

    if (http.parse_header() < 0) return -2;
    switch (http.get_status_code()) {
        case 200:  // HTTP_STATUS_OK
        case 206:  // HTTP_STATUS_PARTIAL_CONTENTS
        case 300:  // HTTP_STATUS_MULTIPLE_CHOICES
        case 304:  // HTTP_STATUS_NOT_MODIFIED
            break;
        case 301:  // HTTP_STATUS_MOVED_PERMANENTLY
        case 302:  // HTTP_STATUS_MOVED_TEMPORARILY
        case 303:  // HTTP_SEE_OTHER
        case 307:  // HTTP_STATUS_TEMPORARY_REDIRECT
            {  // redirect
                task->fileSize = -1;  // if not, the new location's filesize is wrong
                const char *location = http.get_header("Location");
                if (location == NULL) {
                    // I do not know when this will happen, but no harm
                    location = http.get_header("Content-Location");
                    if (location == NULL) return -1;
                }
                if (strcmp(location, task->url.get_url()) == 0) break;
                if (task->url.reset_url(location) < 0) return -2;
                return S_REDIRECT;
            }
        case 305:  // HTTP_USE_PROXY
            {   // get the content through the proxy
                task->fileSize = -1;  // if not, the new location's filesize is wrong
                return S_REDIRECT;
            }
        case 408:  // HTTP_CLIENT_TIMEOUT
        case 504:  // HTTP_GATEWAY_TIMEOUT
        case 503:  // HTTP_UNAVAILABLE
        case 502:  // HTTP_BAD_GATEWAY
            {   // these errors can retry later
                return -2;
            }
        default:
            return -1;
    }

    // if the page is an active page, we maybe can not get the filesize
    if (task->fileSize < 0) {
        task->fileSize = http.get_file_size();
        if (task->fileSize > 1) {
            // we need test whether the Range header is supported or not
            return -2;
        }
    } else {
        // IIS never return the Accept-Ranges header
        // We need check the Content-Range header for the resuming
        const char *ptr = http.get_header("Content-Range");
        if (ptr) {
            while (*ptr != '\0' && !ISDIGIT(*ptr)) ptr++;
            if (*ptr++ == '1' && *ptr == '-') {
                // get the filesize again for ensure the size
                task->fileSize = 1 + http.get_file_size();
                task->resumeSupported = true;
            }
        }
    }

    const char *filename;
    filename = http.get_header("Content-Disposition");
    if (filename) {
        filename = strstr(filename, "filename=");
        if (filename) {
            filename += strlen("filename=");
            if (task->get_local_file() == NULL) {
                task->set_local_file(filename);
            }
        }
    }


    if (task->get_local_file() == NULL &&  task->url.get_file() == NULL) {
        task->set_local_file("index.html");
    }

    return 0;
};

int HttpPlugin::download(Task& task, Block *block) {
    block->state = STOP;
    if (task.resumeSupported) {
        if (block->downloaded >= block->size) {
            block->state = EXIT;
            return 0;
        } else {
            block->bufferFile.seek(block->startPoint + block->downloaded);
        }
    } else {
        block->bufferFile.seek(0);
        block->downloaded = 0;
    }

    Http http;
    http.set_timeout(task.timeout);
    http.set_log(&debug_log);
#ifdef HAVE_SSL
    if (task.url.get_protocol() == HTTPS) {
        http.set_use_ssl(true);
    }
#endif

    if (task.resumeSupported) {
        // the end is not set for the schedule purpose
        http.set_range(block->startPoint + block->downloaded);
    }

    if (task.url.get_user() != NULL) {
        http.auth(task.url.get_user(),
                task.url.get_password() ? task.url.get_password() : "");
    }

    if (task.get_referer() != NULL) {
        http.header("Referer", task.get_referer());
    } else {
        http.header("Referer", task.url.get_url());
    }

    if (task.get_host() != NULL) {
        http.header("Host", task.get_host());
    } else {
        http.set_host(task.url.get_host(), task.url.get_port());
    }

    if (task.get_ua() != NULL) {
        http.header("User-Agent", task.get_ua());
    } else {
        http.header("User-Agent", USER_AGENT);
    }

    if (task.proxy.get_type() == HTTP_PROXY) {
        if (http.connect(task.proxy.get_host(), task.proxy.get_port()) < 0) {
            return -2;
        }
        if (task.get_host() == NULL) {
            http.set_host(task.url.get_host(), task.url.get_port());
        }
        if (task.proxy.get_user() != NULL) {
            http.proxy_auth(task.proxy.get_user(),
                    task.proxy.get_password() ? task.proxy.get_password() : "");
        }
        if (http.get(task.url.get_url()) < 0) {
            return -2;
        }
    } else {
        if (http.connect(task.url.get_host(), task.url.get_port()) < 0) {
            return -2;
        }
        if (http.get(task.url.get_encoded_path()) < 0) {
            return -2;
        }
    }

    if (http.parse_header() < 0) return -2;
    // the service maybe unreachable temply
    // some servers alway return 302, so nasty
    if (http.get_status_code() >= 400) return -2;

_re_retr:
    block->state = RETR;
    if (block->bufferFile.retr_data_from(&http, &block->downloaded,
                block->size - block->downloaded) < 0) {
        block->state = STOP;
        return -2;
    }

    if (task.resumeSupported && block->downloaded < block->size) {
        block->state = STOP;
        return -2;
    }

    block->state = WAIT;
    usleep(500000);
    if (block->state == WAKEUP) goto _re_retr;
    block->state = EXIT;
    return 0;
};

int HttpPlugin::get_dir_list(Task& task, const char *tempfile) {
    return 0;
};

